Most of us would be surprised to find a guy reading Gossip Girls or Princess Diaries. There's no denying that there are specific trends when it comes to gender preferences. There's always been a big debate as to whether such preferences are inherent or a social construct, and pointing out differences between the genders has sometimes been confused for forms of discrimination. I would argue that acknowledging differences does not mean you are biased towards a particular gender -- preferential treatment does.

I thought I'd touch on some of the research on the topic of gender differences, particularly findings that might have an impact on reading preferences.

Research suggests:

there are actual biological differences between male and female brain development that affect cognitive ability. MRI scans show that children's brains develop in difference sequences and times

MRI scans reveal that the development in the area of brain for language (reading, verbal fluency, writing) and recognizing faces in the average 5 year old boy is 2-3 years behind a girl of the same age

Development in the area of the brain that deals with Math and science in an average girl can mature 4-8 years later than an average boy

It appears that there are more connections between the parts of the brain that deal with language and emotion in females - this might explain why most women like to read and talk about emotions more

There seems to be less cross hemisphere activity in boys' brains than in girls when working on certain tasks, in effect, boys' brains are less engaged during certain tasks and extra sound, colour, motion and physical stimulation can enhance the experience. This may explain why boys like non-fiction (quick tidbits of information) and action driven plots.

I think what we need to realize is that biological factors mean each gender learns differently due to their different strengths. Boys might be more interested in topics that have to do with math and science because they understood those better than girls at an earlier age. Girls might be more interested in narrative and expository texts focusing on the emotional development of characters because their brains are wired for this.

This is not to say biology determines our interests, but rather that it can play a role in addition to personal experience and environmental and social conditions. Of course there will always be exceptions where certain girls are brilliant at math and science and boys are exceptional readers at a young age. Note too that biological differences can often be overcome by extra study. The main point here is that it is important to recognize that different preferences exist and to shape a library collection to meet these needs.